The candidate of this K23 Mentored Patient-Oriented Career Development Award application, John J. Mariani, MD, requests support for a five-year program of training and research aimed at developing expertise in the development, execution, and analysis of pharmacotherapy clinical trials for substance use disorders. Dr. Mariani proposes career development activities that build on his background in psychiatry and clinical research and capitalize on the resources of Columbia University and the New York State Psychiatric Institute to aid him achieving the long-term goal of becoming an independent investigator. As part of a comprehensive educational plan, Dr. Mariani will receive intensive mentoring and didactics in biostatistics, clinical trial study design and logistics, the ethical conduct of research, manuscript preparation, and grant writing and management. The short-term goals are to acquire skills in the design, operation and analysis of a randomized controlled trial. Dr. Mariani will reach these goals by engaging in an integrated educational program of didactics and research. The proposed research plan consists of a randomized double-blind, placebo-controlled trial of gabapentin in the treatment of benzodiazepine-abusing opioid-dependent patients receiving methadone maintenance treatment. It is estimated that approximately one-third of patients in methadone maintenance treatment abuse benzodiazepines and there are no known effective treatments. Gabapentin, an antiseizure medication with a wide safety margin, has shown promise in the treatment of alcohol-related disorders. Since benzodiazepines and alcohol have similar mechanisms of actions, gabapentin is an excellent candidate for study as a potential pharmacotherapy for benzodiazepine use disorders. Conduct of this clinical study will build on Dr. Mariani's prior work in evaluating the use of anticonvulsant agents as pharmacotherapies for substance use disorders. The goal of this K23 Mentored Patient-Oriented Career Development Award is to provide Dr. Mariani with the necessary training and research experience to become an independent investigator. Relevance to Public Health: Benzodiazepine abuse is a common problem in opioid-dependent patients receiving methadone maintenance treatment for which there are no known effective treatment. Development of an effective treatment strategy would have a direct positive impact on public health.